Cable operating means for power shovels



F. D. GRAHAM 2,233,007

CABLE OPERATING MEANS FOR POWER SHQVELS Filed Feb. 14, 1940 /NVENTOR: 6r

ATTORNEYS. L

' Patented Feb. 25, 1941 T Frederick Dwight Graham, Milwaukee, wieL, as-

signor to Koehring Company, Milwaukee, Wis

a corporation Application February 14, 1940, Serial No. 318,931

3 Claims.

out of the dipper or shovel with respect to the lil boom. Lifting movement is imparted to the shovel dipper by means of a power actuated cable which is reeved over sheaves connected to the outer end of the boom and to the shovel dipper. Heretofore it has been necessary to construct the I boom in a skeleton-like manner to provide a cutaway or depressed portion at the outer end of 'the boom in order to prevent engagement of the lifting cable with a part of the boom structure. The necessity of such a boom construction has been particularly emphasized when using a socalled threepart hoist line arrangement of the lifting cable in which the lifting cable is passed partially around one of the sheaves mounted at the outer end of the boom.

This invention has for its primary object the provision of a novel tackle system for imparting lifting movement to the dipper or shovel, and which will permit the use of a boom which is sumtantially solid or enclosed to its outer end.

The invention also contemplates an arrangement of hoisting mechanism which will eiiectively prevent contact of the lifting cable with the outer end of the boom.

In carrying out these features, an auxiliary sheave is employed and mounted on the upper surface of the boom at a point spaced inwardly of the end thereof. The cable is' reeved around the auxiliary sheave and passed over the sheaves mounted on the outer end of the boom. The use 0 of the auxiliary sheave permits the passing of the lifting cable over the sheaves located at the outer end of the boom in a manner which will prevent the cable from coming in contact with any part of the boom. The hoisting mechanism efliciently permits the change from a three-part hoist line arrangement of the lifting cable to a two-part hoist line arrangement without altering the construction of the hoisting mechanism and with little loss of time in efiecting such change.

The above and other objects will become apparent during the course of the following description.

In the drawing, I have shown a preferred embodiment of my invention. In this showing:

Figure 1 is a plan view illustrating the application of this invention to a conventional type power shovel.

Figure 2 is a perspective view of the boom, a part thereof being broken away, shown in Figure 1, illustrating the mechanism by which a hoisting movement is imparted to the dipper.

Figure 3 Ba diagrammatic viewillustrating a three-part hoist line arrangement of the hoist mechanism, as shown in Figure 2; and,

.Figure 4 is a diagrammatic view illustrating a two-part hoist line arrangement of the hoist mechanism.

For the purpose of the present description, the details of the shovel construction will not be described with particularitysince this invention relates only to the shovel hoist mechanism which permits the use of a solid or enclosed rigid boom structure.

Referring to Figure 1, the numeral II) indicates a traction base supporting a swing body or turntable II. A boom [2 is pivotally secured to the turntable II and is operated in the usual well known manner by mechanism which is-not shown.

A shovel or dipper i3 is provided with dipper carrying members or sticks l4 and is secured to the boom l2 by saddle blocks I 5 pivotally mounted on a shipper shaft I6 mounted on the boom l2. A shipper drum l1 and pinions l8, controlling the crowding out and racking in of the dipper l3, are keyed to the shipper shaft IS. The spaced dipper sticks are provided with racks 19 engageable with the pinions I8 to cause the crowding out and racking in movement of the dipper l3. The shipper drum I| and movement of the dipper I3 is controlled by a cable (not shown) actuated by power mechanism located in the turntable H in a well known manner.

In order to impart a lifting movement to the .dipper l3, a sheave 20 is secured to the dipper bail block 2|. A sheave 22 is mounted on the upper surface of the boom l2 and three axially aligned sheaves 23 are mounted on the outer end of the boom l2.

A cable 24 is reeved with respect to the sheaves 20 and 22 and is passed over the sheaves 23. The

cable 24 has one end anchored to an anchor block that the sheaves 29 and 22 ina sense form a block and tackle system of which the sheave 20 is the movable pulley. To provide a three-part hoist line arrangement of the'cable. 24 for the dipper 13, it will be noted that the cable 24 is passed over the central sheave 23 reeved around the sheave 20 and then passed over an end sheave 23. The cable 24 is then reeved around the auxiliary sheave 22 and passed over another end sheave 23 and then fastened to the anchor block 25. struction and arrangement that the sheaves 23 merely form supporting members for the cable 24 which rides on the outer portion of the grooves formed in the sheaves 23 to maintain the cable 24 out of engagement with the boom I2.

Heretofore the practise in providing a threepart hoist line arrangement of the lifting cable has been to reeve the lifting cable around one of the sheaves 23 in order to return the cable to the dipper bail block sheave 20 for anchoring.

The dotted line 21 in Figure 1 indicates the position of the cable 24, in such an arrangement of the hoist mechanism, where the auxiliary sheave 22 is not employed. As the dipper I3 is racked in, the angle between the innerstrand of the lifting cable as indicated by the dotted line 21 and the beam 12 would be decreased. Accordingly, in such a construction it was necessary to make the boom i2 substantially hollow in order that the part 21 of the lifting cable would not 'frictionally engage parts of the boom l2.

By the employment of the auxiliary sheave 22 it will be apparent that the cable 24 will always be positioned tangentially with respect to the outer portions 28 of the supporting sheaves 23. The cable 24 is thereby effectively prevented from engagement with the boom l2 and a solid boom may be employed in place of the skeleton-like structure. used heretofore.

Referring to Figure 4, I have shown the arrangement of the hoist mechanism of this invention when it is desired to use a two-part hoist line. When using the apparatus in this manner, the cable 2G is reeved about the auxiliary sheave 22 and achored to itself by a fastening device 29 or by other conventional means instead of returning it over one of the sheaves 23 for anchoring to the bail block sheave 20 as is the case when using a. three-part hoist line arrangement. fore, be apparent that the above construction provides a novel arrangement of hoist mechanism for a three-part hoist line which is also capable of being used as a two-part hoist or single part hoist line as desired, without modifying the general arrangement of sheaves availed of for both purposes.

It will be apparent from this 0011-.

It will, thereing sheave connected to said shovel, three sepa- 3 rate axially aligned sheaves mounted on the outer end of said boom, and a cable reeved with respect to said first mentioned and hoisting sheaves and having parts thereof passing over and in engage-- ment with each of said axially aligned sheaves, 3

and means for anchoring an end of said cable whereby a hoisting movement may be imparted to said shovel by said cable.

2. In apparatus of the character described, the

combination of a boom, a shovel mounted on said 5 boom for movement relative thereto, and a threepart hoist line tackle system for importing a hoisting movement to said shovel comprising a fixed sheave mounted on said boom at a point spaced inwardly of the end thereof, a movable sheave 1 connected to-said shovel, three separate guide sheaves mounted on the outer end of said boom, and a cable reeved with respect to said fixed and movable sheaves and having parts thereof passing over and in engagement with each of said guide sheaves, and means for anchoring an end of said cable with respect to said movable sheave whereby said cable will be effective to impart a hoisting movement to said movable sheave and the cable connected thereto.

3. In apparatus of the character described, the combination of a boom, a shovel mounted on said boom, and a three-part hoist line pulley system for imparting a hoisting movement to said shovel comprislngan auxiliary sheave mounted on saidboom at a point spaced inwardly of the end thereof, a hoisting sheave connected to said shovel, three separate guide sheaves mounted on the outer end of said boom, a cable, and a hoisting drum operable for reeling said cable, said cable having an end thereof secured to said hoisting drum and the other end anchored adjacent to said hoisting sheave, the portion of said cable intermediate said ends passing from said drum over one of said guide sheaves and thence around said hoisting sheave, thence over a second of said guide sheaves, thence around said auxiliary sheave and over a third of said guide sheaves to its anchor, the cable arrangement being such that upon operation of said drum to reel said cable a hoisting movement will be imparted to said shovel.

FREDERICK DWIGHT GRAHAM.

CERTIFICATE OF CORRECTION.

Patent No. 2,255,007. February 2 19t FREDERICK DWIGHT GRAHAM.

It is hereby certified that error appears in the printed specification ofthe above numbered patent requiring correctionas follows: Page 2,- second column, line 22, claim 2, for the word "importing" read -imparting--;

.and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 8th day of April, A. D. 19in.

Henry Van Arsdale,

(Seali Acting Commi esioner of Patents. 

